Rajbeer Singh Sangha, MD
Xu X, Chen X, Zhang J, Zheng Y, Sun G, Yu X, et al. Comparison of the Tada Formula With Software Slicer: Precise and Low-Cost Method for Volume Assessment of Intracerebral Hematoma. Stroke. 2014
The volume of ICH has been validated to be an important independent predictor for prognosis. In order to calculate the volume of ICH, the ABC/2 formula has been widely used for bedside estimation of hematoma volume however given the nature of its calculation it is subject to error. The authors of this study utilized 3D Slicer, which is a free open source software platform for biomedical research to validate the size-dependent and shape-dependent estimation error of the ABC/2 formula by comparison with 3D Slicer. 3D Slicer not only supports versatile visualizations but also provides advanced function, such as automated segmentation and registration for various applications.
The CT scans of 294 patients were analyzed and the mean hematoma volume was 58.41±37.83 cm3 with the ABC/2 formula and 50.38±31.93cm3 with 3D Slicer method (t=10.010, P<0.01). When divided by hematoma shape, the ABC/2 formula produced a significant estimation error of 3.33 cm3, 7.19 cm3, and 29.39 cm3 in regular, irregular, and multi-lobular hematomas (p<0.05 in each group). The percent deviation was significantly larger in irregular and multi-lobular hematomas compared with regular hematomas (H=63.052, p<0.001).
The authors suggest that inaccurate hematoma volumes may influence treatment decisions as well as clinical trials in terms of the surrogate endpoints. It is difficult to say how much clinical treatment decisions are affected by the degree of inaccuracy in the ABC/2 method and perhaps that can be a future study. If the 3D slicer is an easily accessible mode of calculating hematoma volume it should be utilized readily. However accessibility and ease of use is always the key components to adopting a new methodology. I would be curious to see how this application is utilized and applied going forward and whether new technologies do address the need for a higher level of accuracy when it comes to calculating hematoma volumes.